This is a note to let you know that I've just added the patch titled IB/cm: Avoid a loop when device has 255 ports to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ib-cm-avoid-a-loop-when-device-has-255-ports.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 96ca39a5f9c957e532b026424448095240641bbf Author: Parav Pandit <parav@xxxxxxxxxx> Date: Wed Jan 27 17:00:08 2021 +0200 IB/cm: Avoid a loop when device has 255 ports [ Upstream commit 131be26750379592f0dd6244b2a90bbb504a10bb ] When RDMA device has 255 ports, loop iterator i overflows. Due to which cm_add_one() port iterator loops infinitely. Use core provided port iterator to avoid the infinite loop. Fixes: a977049dacde ("[PATCH] IB: Add the kernel CM implementation") Link: https://lore.kernel.org/r/20210127150010.1876121-9-leon@xxxxxxxxxx Signed-off-by: Mark Bloch <mbloch@xxxxxxxxxx> Signed-off-by: Parav Pandit <parav@xxxxxxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c index 5afd142fe8c78..8e578f73a074c 100644 --- a/drivers/infiniband/core/cm.c +++ b/drivers/infiniband/core/cm.c @@ -4332,7 +4332,7 @@ static int cm_add_one(struct ib_device *ib_device) unsigned long flags; int ret; int count = 0; - u8 i; + unsigned int i; cm_dev = kzalloc(struct_size(cm_dev, port, ib_device->phys_port_cnt), GFP_KERNEL); @@ -4344,7 +4344,7 @@ static int cm_add_one(struct ib_device *ib_device) cm_dev->going_down = 0; set_bit(IB_MGMT_METHOD_SEND, reg_req.method_mask); - for (i = 1; i <= ib_device->phys_port_cnt; i++) { + rdma_for_each_port (ib_device, i) { if (!rdma_cap_ib_cm(ib_device, i)) continue; @@ -4430,7 +4430,7 @@ static void cm_remove_one(struct ib_device *ib_device, void *client_data) .clr_port_cap_mask = IB_PORT_CM_SUP }; unsigned long flags; - int i; + unsigned int i; write_lock_irqsave(&cm.device_lock, flags); list_del(&cm_dev->list); @@ -4440,7 +4440,7 @@ static void cm_remove_one(struct ib_device *ib_device, void *client_data) cm_dev->going_down = 1; spin_unlock_irq(&cm.lock); - for (i = 1; i <= ib_device->phys_port_cnt; i++) { + rdma_for_each_port (ib_device, i) { if (!rdma_cap_ib_cm(ib_device, i)) continue;